Gas tanks

Lag time fast systems

Sample pressure - fast NOx

Surface O3 concentrations

- Surface O3 mean diurnal cycle


Fast NOx data
TO DO list:
* Puff system.
* Check fast NOx calibration data.
* Start CO2 on autosampler #1.
* Calibration tank for enclosures.
Tuesday, June 4th
Daily checks
- Lab temperature = 23.0°C, AC temperature = 68F. Changed AC temperature to 65F at 9:19am local time.
- Case temperature: fast O3 = ~25.1°C, fast NOx = ~22.5°C.
- PMT temperature: fast O3 = -34.4°C, fast NOx = -31.7°C.
- Changed drierite.
- Fast O3: OK, NO flow rate OK.
- Fast NOx: OK but high counts (5000-5500).
- Gas tanks: OK.
- Fast O3 laptop synchronized with time.nist.gov at 8:22 AST.
Enclosures
- Enclosure #2 has been running all night, ends at 3:30pm AST. Saved HOBO#2 data at 9:22am AST. At the end of the sequence: checked autosampler flowrate (set = 250 mL/min, Defender = 275 mL/min). Enclosure moved to a different location at ~3:40pm AST.
- Prepared enclosure #1. Checked flow rate pump (27 L/min) and leak check on the line (autosampler’s flow rate dropped to 0 when cap on line in bag). HOBO#1 started. Checked flow rate autosampler: set = 200 mL/min, Defender = 265 mL/min. We can start sampling BVOCs + CO2 tomorrow.

GC/MS calibration
Using Catie’s tanks.
* Calib B tank: samples TL_20190604_01 and TL_20190604_02.
* Calib A tank: samples TL_20190604_03 and TL_20190604_04.
Monday, June 3rd
Daily checks
- Lab temperature = 23.0°C, AC temperature = 68F.
- Case temperature: fast O3 = ~24.7°C, fast NOx = ~22.5°C.
- PMT temperature: fast O3 = -35.0°C, fast NOx = -32.2°C.
- Drierite: OK, change it probably later today or tomorrow morning.
- Fast O3: OK, NO flow rate OK.
- Fast NOx: OK but high counts (5000-5500).
- Gas tanks: OK.
- Fast O3 laptop synchronized with time.nist.gov at 8:18 AST.
Enclosure #2
- Autosampler #2 connected to Anssi’s sample line in the tent.
- Put a cap on sample line in the bag (remove O3 scrubber) and autosampler’s flow rate decreased to 0.02 L/min. No leak on the line.
- valves temp = 40°C, cartriges temp = 35°C.
- Set of 10 cartriges:
90987 - 6/3/2019 15:00 to 6/3/2019 17:00
4545 - 6/3/2019 17:30 to 6/3/2019 19:30
90971 - 6/3/2019 20:00 to 6/3/2019 22:00
781 - 6/3/2019 22:30 to 6/4/2019 00:30
90951 - 6/4/2019 1:00 to 6/4/2019 3:00
4645 - 6/4/2019 3:30 to 6/4/2019 5:30
655 - 6/4/2019 6:00 to 6/4/2019 8:00
4536 - 6/4/2019 8:30 to 6/4/2019 10:30
259 - 6/4/2019 11:00 to 6/4/2019 13:00
90601 - 6/4/2019 13:30 to 6/4/2019 15:30
Sunday, June 2nd
- Restarted GC/MS sequence:
TL_20190601_17 to TL_20190601_44 are ambient air samples.
- The fast NOx counts were high again (~6000). Turned off PMT HV, disconnected and reconnected signal/PMT cables -> Still ~6000 counts. I don’t know why.
Saturday, June 1st
- O3 sonde and Kestrel on tower for intercomparison: 8:58am to 2:00pm AST. The data compare fairly well.
Daily checks
- Lab temperature = 22.1°C, AC temperature = 68F.
- Case temperature: fast O3 = ~22.9°C, fast NOx = ~18.1°C.
- PMT temperature: fast O3 = -35.3°C, fast NOx = -34.2°C.
- Drierite: OK.
- Fast O3: OK, NO flow rate OK.
- Fast NOx: OK.
- Gas tanks: OK.
- Fast O3 laptop synchronized with time.nist.gov at 8:17 AST.
Puff system
3 injections at (fast NOx time):
2019-06-01 08:34:35
2019-06-01 08:36:05
2019-06-01 08:37:56
Enclosure #2
I checked HOBO data.


GC/MS
Detlev made changes to the method yesterday (BVOC_SCAN_SIM_190531.M): the oven stays at 120°C between samples now and decreases to 35°C when the run starts (the lower we go, the better the earlier peaks such as isoprene are). Today, we increased the max temperature of the method to 260°C instead of 250°C. Note that we did not change the method’s name, still BVOC_SCAN_SIM_190531.M.
Today we updated the SIM time segments:
We also updated the peaks for each segments:
* alkanes + CFC-11: 41, 43 (alkanes) 101, 103 (CFC-11).
* isoprene: 67, 68.
* CFC-113: 101, 151.
* metacrolein + MVK: 41, 55, 70.
* aromatics (benzene, toluene, xylenes): 78, 91, 106.
* MT: 68, 93, 121, 136.
* SQT: 204, 91, 93, 119, 69.
- We disconnected the GC/MS line (tee that also goes to slow O3). The GC/MS is now connected to the enclosure #2 outside. We checked that there’s not leak putting a cap on the line outside.
Sample TL_20190601_01.
TL_20190601_02 is NPL.
BVOC bags
Kaixin and Jacob collected ambient air samples in 4 different bags. Catie analyzed them on the TOF.